This invention relates to a current control circuit with a current proportional circuit and more particularly to a current control circuit in which a flowing direction of a current is switched by a switching signal and the values of the switched current have a proportional relationship.
A current control circuit which an output signal is controlled by an input binary signal is applicable to various types of circuits, such as a digital-analog converter, a phase comparator and a unipolar-bipolar converter. When an input binary signal is supplied to an input terminal of the current control circuit, a current flowing a load coupled with an output terminal of the current control circuit is switched in a direction. However, it has been difficult to maintain a propotional relationship between the values of the switched current in a conventional current control circuit. Further, the configuration of the current control circuit has been complicated so that is has been unsuited in an integrated circuit and high in cost.